It provides a general command system which can be used
in a variety of environments, including GUI applications
and command line utilities. This is inspired by elements
of the Lisp Machine, the Common Lisp Interface Manager
(CLIM), router command line interfaces, and the TOPS-20
command line among other things.

Commands can be defined and grouped into command tables.

Commands can be hooked up with a Parser for implementing
command line interfaces with completion and parameter validation.

This library is in the early stages of development and
not everything works yet.